Authorities say the man has used a gun in at least 16 incidents at various businesses since December 9.
The most recent happened Tuesday night at a KFC in Shirley and a Best Express in Lake Ronkonkoma. The suspect has targeted Subway restaurants in six other incidents.
The suspect is described as male, possibly Hispanic, between 5-foot-6 and 5-foot-10 who wears a hooded sweatshirt, dark-colored scarf and mask covering his face.
Anyone with information about these incidents is asked to call anonymously to Crime Stoppers at 1-800-220-TIPS. All calls will remain confidential.
